1. Field of the Invention
The present invention relates to a grid that aids in designating the location and collection of evidence. More particularly, the present invention relates to a transportable preset grid for the measuring and designating the location of evidence, such as buried or surface artifacts or human remains at a crime scene.
2. Description of Related Art
It is accepted and standard to provide a “grid” at an outdoor or otherwise large area such as a crime scene, archeological dig or other scenes to create a working area in which evidence, artifacts, etc. can be accurately catalogued as to its precise location at the time of its discovery. (This is useful in scenes that are not contained within a structure, vehicle or other site wherein evidence or other items can easily be located off of permanent measurable datum points.) The grid is labeled by row and column (Column A, B, C . . . Row 1, 2, 3 . . . ), and the location of any evidence found is denoted by the section of the grid in which it was found. If a question arises at a later date, such as later in the investigation or at trial, as to where a piece of evidence was located and its relevance to the rest of the scene, the scene can be “re-enacted”.
For example, at the site where a body or other evidence is potentially buried, an investigative team establishes the probable location of evidence—and over that area constructs a grid. The following describes how establishing a grid is currently typically carried out.
First, the investigators determine the size of the area to be gridded. At least one datum point must be determined—something permanent that can be referred to at a future date. A wooden stake is driven into the ground at the outside corner of the area of interest and measured off of the datum point(s). Then, a mason's line is tied to the first stake, measured out the desired length and a second stake is driven into the ground. The line is then tied off on the second stake. A line level is then used to check the level of the string, and the string is raised or lowered to achieve level.
Then the second side is measured out. But before the third stake can be placed, the second side must be made square to the first using either the hypotenuse of the size of the grid being strung, or the 3-4-5 rule. To use the hypotenuse of the desired area, for example 12 feet by 12 feet, Pythagorean's Theorem (a2+b2=c2) is used to determine the hypotenuse. In this case, the hypotenuse would be 16.97 feet. One pair of investigators hold the measuring tape for the length of the side while another pair measure out the hypotenuse, all persons ensuring that the measurements are accurate and line up. The 3-4-5 rule (which also uses Pythagorean's Theorem) states that if one side of a right triangle equals 3 feet and the second side equals 4 feet, then the hypotenuse equals 5 feet. Again, it requires multiple persons to hold the measuring tapes (this time three of them) and move the lines until square is achieved. While the strings and tape measures are being held, it must be visually checked that no lines are being bent and that the lines are all straight. This process is repeated for the establishing the third side of the grid, and if all goes well, the fourth side should be the correct length. Ideally, square is then double-checked by measuring both hypotenuses and ensuring they are the same length. If not, adjustments can be made at this time by relocating the stakes at the corners. Level is re-checked, then the process of measuring and locating the inside lines of the grid begins. After all is said and done, much effort and manpower has been expended. In current protocol, mason line is typically used, which is affected greatly by time, stress and the elements. These grids can potentially need to be in place for days at a time, and when the lines sag they need to be tightened and all measurements re-checked.
Inherent shortcomings associated with this method are that it is complicated, requires multiple personnel to carry out and relies heavily on human nature and interpretation. An individual's training in accurate measurement, their eyesight, their level of fatigue, their overall work ethic and environmental factors such as weather and wildlife are all factors that could possibly add to inaccuracies in the construction of the grid, and therefore the locating of evidence. There can always be a significant margin of error in this process. In addition, it takes a significant amount of time to string a grid, and the passage of time can be detrimental to the condition of the evidence and delay its discovery. There is a need for a device that can be easily transported and can be quickly, accurately and consistently set up and be confidently relied upon.